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Although the role of ERα in regulating bone metabolism has been extensively studied, ERβ has been largely dismissed as a relevant modulator of bone mass. Previous studies examining ERβ utilized a germline knockout mouse expressing transcript variants of ERβ and displaying systemic hormonal changes that confounded interpretation of the skeletal phenotype. Thus, we used a conditional ERβ mouse model to achieve deletion of ERβ specifically in early osteoprogenitor cells using the Prx1-Cre driver. We observed marked increases in the trabecular bone volume fraction (of 58% [p less then 0.003] and 93% [p less then 0.0003] in 6- and 12-week-old female ERβ(Prx1-CKO) mice, respectively) but no changes in cortical bone. Serum estradiol and IGF-I levels were unaltered in ERβ(Prx1-CKO) mice. Bone formation and resorption indices by histomorphometry and serum assays were unchanged in these mice, suggesting that alterations in bone turnover may have occurred early in development. However, the ratio of colony-forming unit-osteoblasts (CFU-OBs) to CFU-fibroblasts (CFU-Fs) was increased in bone marrow cultures from ERβ(Prx1-CKO) compared with control mice, indicating increased differentiation of osteoblast precursor cells into osteoblasts in ERβ(Prx1-CKO) mice. Detailed quantitative polymerase chain reaction analyses of 128 genes in 16 prespecified pathways revealed significant downregulation of 11 pathways in ERβ(Prx1-CKO) mice. Thus, deletion of ERβ specifically in osteoblast lineage cells, in the absence of all splice variants, increases trabecular bone mass and modulates multiple pathways related to bone metabolism. These findings suggest that pharmacological inhibition of ERβ in bone may provide a novel approach to treat osteoporosis.Quaternary amine of diethylaminoethyl rosin ester (QRMAE), chemically synthesized biocompatible rosin based cationic surfactant, has various biological applications including its use as a food product additive. In this study, we examined the amorphous aggregation behavior of mammalian serum albumins at pH 7.5, i.e., two units above their isoelectric points (pI ~5.5), and the roles played by positive charge and hydrophobicity of exogenously added rosin surfactant QRMAE. The study was carried out on five mammalian serum albumins, using various spectroscopic methods, dye binding assay, circular dichroism and electron microscopy. The thermodynamics of the binding of mammalian serum albumins to cationic rosin modified surfactant were established using isothermal titration calorimetry (ITC). It was observed that a suitable molar ratio of protein to QRMAE surfactant enthusiastically induces amorphous aggregate formation at a pH above two units of pI. Rosin surfactant QRMAE-albumins interactions revealed a unique interplay between the initial electrostatic and the subsequent hydrophobic interactions that play an important role towards the formation of hydrophobic interactions-driven amorphous aggregate. Amorphous aggregation of proteins is associated with varying diseases, from the formation of protein wine haze to the expansion of the eye lenses in cataract, during the expression and purification of recombinant proteins. This study can be used for the design of novel biomolecules or drugs with the ability to neutralize factor(s) responsible for the aggregate formation, in addition to various other industrial applications.

To evaluate the effect of supplemental scleral buckle (SB) in pars plana vitrectomy (PPV) for rhegmatogenous retinal detachment.

MEDLINE, EMBASE, and CENTRAL were searched to identify studies comparing PPV with supplemental SB (PPV + SB) to PPV alone for the repair of rhegmatogenous retinal detachment. The outcome measures were primary and final reattachment rates, and postoperative complications. Odds ratio with 95% confidence interval in random effects for the comparison of outcomes between PPV + SB and PPV alone was calculated.

Ten studies consisting of 1,704 patients were included. Meta-analysis showed that the overall primary reattachment rate was significantly higher in PPV + SB than PPV alone (odds ratio, 1.70; 95% confidence interval, 1.21-2.39; P = 0.002). The final reattachment rate was equally high in both groups. Postoperative development of epiretinal membrane was more frequent in PPV + SB than in PPV alone (odds ratio, 1.89; 95% confidence interval, 1.30-2.76; P = 0.001), whereas no significant difference in postoperative development of macular edema, proliferative vitreoretinopathy, or elevation of intraocular pressure was found.

Supplemental SB increases the primary reattachment rate in PPV for rhegmatogenous retinal detachment, although final reattachment rate was equally high with or without SB.

Supplemental SB increases the primary reattachment rate in PPV for rhegmatogenous retinal detachment, although final reattachment rate was equally high with or without SB.

To investigate Wnt3a and vascular endothelial growth factor (VEGF) levels in the vitreous fluid of patients with proliferative diabetic retinopathy (PDR) and to examine their correlation with PDR activity.

Vitreous samples from 45 eyes with PDR and 28 eyes with nondiabetic macular disease were collected. Active PDR was present in 24 patients and inactive PDR in 21 patients, according to retinal neovascularization. The Wnt3a and VEGF level of vitreous fluid samples were measured by enzyme-linked immunosorbent assay.

Comparison revealed that mean intravitreal levels of Wnt3a increased significantly in PDR eyes compared with control eyes (13.55 ng/mL vs. AZD7648 order 1.57 ng/mL, P < 0.001). The mean VEGF concentrations in the vitreous fluid of patients with PDR were also higher than those in nondiabetic controls, with the values being 723.21 pg/mL and 20.81 pg/mL, respectively (P < 0.001). In addition, vitreous concentrations of Wnt3a and VEGF were significantly higher in active PDR than in eyes with inactive PDR (P = 0.016 and P = 0.008, respectively). Furthermore, a significant positive correlation was detected between Wnt3a and VEGF levels in the vitreous.

Intravitreous levels of Wnt3a and VEGF in patients with PDR are increased and correlated mutually. Wnt3a may be an important player in the development of diabetic retinopathy and its activity in vitreous fluid can be biomarker of PDR.

Intravitreous levels of Wnt3a and VEGF in patients with PDR are increased and correlated mutually. Wnt3a may be an important player in the development of diabetic retinopathy and its activity in vitreous fluid can be biomarker of PDR.

To determine baseline factors that can predict the response of pigment epithelial detachments (PEDs) in neovascular age-related macular degeneration to treatment with intravitreal bevacizumab (IVB).

Patients with newly diagnosed neovascular age-related macular degeneration and PED who were treated exclusively with IVB were included. Response to treatment was defined by change in PED volume (determined using spectral-domain optical coherence tomography). PEDs were classified as either predominantly serous or fibrovascular. Multivariable regression and receiver operating characteristic analyses were performed.

A total of 48 eyes were identified (mean follow-up time 73 weeks). Overall, the response to the first IVB treatment was predictive of the response to treatment at the final visit (P = 0.015). Serous PEDs had a greater decrease in volume at the final visit (P = 0.008). With respect to both PED types, a decrease in PED volume of 21% after the first IVB treatment was predictive of an overall decrease indothelial growth factor agent should be considered.

To compare the efficacy of a mixture of silicone oil and perfluorohexyloctane (Densiron 68) with C2F6 gas endotamponade in the retreatment of persistently open full-thickness macular holes.

In this prospective randomized study, 21 consecutive patients who were unsuccessfully operated on for large idiopathic full-thickness macular hole were randomly assigned to undergo a second vitrectomy with 20% perfluoroethane gas (C2F6, Group A) or with Densiron 68 tamponade (Group B).

Endpoint (12 months) full-thickness macular hole closure rate by spectral domain optical coherence tomography and logMAR corrected distance visual acuity.

postoperative adverse events.

The mean diameter of macular holes before the second pars plana vitrectomy was 680.3 ± 120.8 μm and 740.5 ± 105.3 μm in Groups A and B, respectively (P = 0.237); mean preoperative corrected distance visual acuity was 0.96 ± 0.36 logMAR and 1.12 ± 0.35 logMAR, respectively (P = 0.315). Endpoint full-thickness macular hole closure was obtained in 30% of patients (3/10) in Group A and in 82% (9/11) in Group B (P = 0.030). Corrected distance visual acuities were, respectively, 0.80 ± 0.25 logMAR and 0.55 ± 0.20 logMAR, with significant intergroup difference (P = 0.019); corrected distance visual acuity increased in Group B only (P = 0.003). No differences in complications were found.

The results indicate that Densiron 68 tamponade could be a useful, safe, and more efficacious method than gas tamponade to retreat persisting macular holes.

The results indicate that Densiron 68 tamponade could be a useful, safe, and more efficacious method than gas tamponade to retreat persisting macular holes.

To determine whether cone photoreceptors are impaired early in macular telangiectasia type 2 (MacTel 2) progression.

Eight patients with MacTel 2 lacking intraretinal cavitation underwent multimodal retinal imaging including adaptive optics. Cone packing metrics were determined in 5 sampling windows at different eccentricities from the fovea. Results were compared with a previously established normative database.

In MacTel 2 eyes, cone density was significantly lower than normal at all eccentricities (P < 0.0001). Mean cone spacing and mean percentage of hexagonally organized cone photoreceptors were respectively significantly larger and lower than normal at all eccentricities (P = 0.0488 and P < 0.0001). In MacTel 2 patients, adaptive optics showed an irregular patchy disturbance of the cone mosaic corresponding to some fragmentation of the interdigitation zone on optical coherence tomography. The ellipsoid zone remained intact in the studied area.

Adaptive optics showed that the macular cone density was lower than normal even outside the telangiectasia in MacTel 2 lacking intraretinal cavitation, although the ellipsoid zone remained intact on optical coherence tomography. These findings do not indicate that the cone density loss is causative of the disease as it might be secondary to Müller cell or rod loss in this area. However, cone density assessment could become a useful parameter to monitor disease progression.

Adaptive optics showed that the macular cone density was lower than normal even outside the telangiectasia in MacTel 2 lacking intraretinal cavitation, although the ellipsoid zone remained intact on optical coherence tomography. These findings do not indicate that the cone density loss is causative of the disease as it might be secondary to Müller cell or rod loss in this area. However, cone density assessment could become a useful parameter to monitor disease progression.

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